1. Field of the Invention
Method and apparatuses consistent with the present invention relate to generating header information of stereoscopic image data, and more particularly, to generating header information including mandatory information for restoring and reproducing original images by decoding encoded stereoscopic images.
2. Description of the Related Art
Various methods of transmitting stereoscopic images have been suggested. For example, stereoscopic images may be transmitted using a multi-view video profile (MVP) method according to Moving Picture Experts Group (MPEG)-2 standards, a depth map transmission method according to MPEG-4 multiple auxiliary component (MAC) standards, or a multi-view coding (MVC) method according to MPEG-4 advanced video coding (AVC)/H.264 standards. Multimedia Application Format (MAF) stereoscopic image data standards are now being established.
FIG. 1 is a diagram illustrating a related art pixel-based stereoscopic image format for transmitting stereoscopic images.
A sheet of an image format for a stereoscopic image is formed by separately sampling left view and right view images in every alternative block and moving the right view image by one pixel so as not to overlap the left view image. The stereoscopic image may be transmitted and received by using a conventional two-dimensional encoder and decoder. The left view and right view images are formed into a sheet of a stereoscopic image format having the same resolution and thus a large number of pixels are lost.
FIG. 2 is a diagram of a related art apparatus for restoring lost pixels of a pixel-based stereoscopic image format.
Pixels that are lost when the stereoscopic image format is generated as illustrated in FIG. 1 have to be restored so that a display device may reproduce an image of original resolution. Original left view and right view images are restored by extracting directional pixel values of a pixel-based sampled image and summing all directional pixel values multiplied by a predetermined weight.
FIG. 3 is a diagram illustrating a reference structure of a related art International Standards Organization (ISO)-based media file format.
In the conventional ISO-based media file format, substantial media data is stored in a media data (mdat) region and information on characteristics of the media data is stored in a movie data (moov) region.
When the image format illustrated in FIG. 1 is transmitted, a fact that overlap information between left view and right view images is large is used in order to improve transmission efficiency. In other words, the transmission efficiency is improved by reducing the amount of transmission data by combining the left view and right view images in pixel units into a sheet of a mixed image to be transmitted.
However, a conventional stereoscopic image format does not include header information in the movie data (moov) region, the header information including a scale function used when the left view and right view images are combined into the mixed image to be transmitted and information regarding whether the mixed image includes camera information of the left view and right view images.
If a stereoscopic image combined into a mixed image having the image format illustrated in FIG. 1 by using a certain combination method is transmitted, an encoding terminal of a reception terminal does not include information on the combination method used by a transmission terminal and thus the mixed image may not be accurately inverse converted to the original stereoscopic image. Accordingly, although the stereoscopic image is losslessly transmitted using the conventional combination method, the stereoscopic image may not be accurately restored because the reception terminal does not include information on the combination method, a scaling method, and so on.